STk is a R4RS Scheme interpreter which can access the Tk graphical
package.  Concretely it can be seen as the John Ousterhout's Tk package
where the Tcl language has been replaced by Scheme.

STk also provides an efficient object oriented system called STklos.
STklos is an extensive OO system with multiple inheritance, generic
functions, multi-methods and a Meta Object Protocol).
